Members including a resin, the surface of which is subjected to metal plating, metal coating or the like, have been used heretofore for giving a metallic-tone design to vehicle interior and exterior components, building interior materials, cases for home electric appliances, and the like. However, when metal plating, metal coating or the like is performed, it is necessary to dispose waste water containing a metal, to take a measure against solvent vapor, and so on. Generally, the yield of these members is not high.
Thus, in recent years, decorative resin molded articles in which a decorative sheet having a metallic tone is laminated on the surface of a resin molded article have been used as the above-mentioned members. For production of a decorative resin molded article, for example, a molding method is used in which a decorative sheet given a design beforehand is integrated with a resin by injection molding.
Some decorative resin molded articles have a complicated surface shape such as a three-dimensional curved surface. Accordingly, decorative sheets are required to have three-dimensional moldability capable of sufficiently following the shape of a decorative resin molded article having a complicated surface shape. Particularly, decorative sheets having a metallic tone often have the problem that adhesion between a resin layer (e.g. base material layer, adhesive layer or the like) formed of a resin and a thin metal film layer formed of a metal is low. When adhesion between a resin layer and a thin metal film layer is low, delamination, floating or the like may occur between the resin layer and the thin metal film layer during molding of a decorative sheet, etc.
For example, Patent Document 1 discloses that a rear anchor layer formed of a resin is provided for improving adhesion between a metal deposition layer of metal deposition transfer material and an adhesive printing layer. In recent years, however, a decorative sheet capable of following the shape of a particularly complicated decorative resin molded article has been desired, and the decorative sheet may be stretched to a maximum draw ratio of 150% or more, for example, at a portion corresponding to the curved portion of the resin molded article. This means that a pan of a decorative sheet having a thin metal film layer is extended by a factor of 2.5 or more, and thus the molding conditions are very hard. Accordingly, conventional decorative sheets having a thin metal film layer cannot follow the shape of such a complicated decorative resin molded article, and have the problem that delamination, floating or the like occurs between a resin layer and a thin metal film layer during molding of a decorative sheet, etc.
Under these circumstances, a decorative sheet having three-dimensional moldability capable of sufficiently following the shape of a decorative resin molded article having a complicated surface shape is desired.